Things that could be added:

- chordii -> chordpro?
- VexTab?
- Verovio?
- tab (https://www.cs.dartmouth.edu/~wbc/lute/AboutTab.html)?
- https://ctan.org/pkg/texchord
- https://tex.stackexchange.com/questions/324828/typesetting-guitar-chord-diagrams-in-a-songbook
- mention kpsewhich

